Structural tube assembly

ABSTRACT

Disclosed herein is a structural tubing assembly such as a fence or gate in which one tubular member is joined to a second tubular member by (1) cutting an elongated opening in the second member, (2) cutting opposing slots in the end of the first member thus forming two locking tabs, (3) inserting the tabs through the opening in the second member, and (4) spreading the tabs, thus securely and rigidly locking the first tubular member to the second tubular member. Preferably, the end of the first tubular member is partially flattened to conform to the shape of the elongated opening in the second member prior to cutting the two opposing slots to form the locking tabs. Optionally, a reinforcing insert such as a tube of proper size is pressed into the opening between the spread tabs to strengthen the connection.

Umted States Patent [1 1 [111 3,776,523

Weiland Dec. 4, 1973 STRUCTURAL TUBE ASSEMBLY 3,180,663 4/1965 Lehmann287/56 x Inventor: Edward E. w Union Lake 3,348,699 10/1967 Mealmg287/56 X Mich. FOREIGN PATENTS OR APPLICATIONS 73 Assigneez UniversalFence Inc Highland 254,347 9/1964 Australia 287/56 Mich.

[ 1 Filed: p 1972 Primary ExammerDenms L. Taylor Appl. No.: 248,253

Related US. Application Data Attorney-Joseph D. Odenweller [5 7 ABSTRACTDisclosed herein is a structural tubing assembly such as a fence or gatein which one tubular member is joined to a second tubular member by (1)cutting an elongated opening in the second member, (2) cutting opposingslots in the end of the first member thus forming two locking tabs, (3)inserting the tabs through the opening in the second member, and (4)spreading the tabs, thus securely and rigidly locking the first tubularmember to the second tubular member. Preferably, the end of the firsttubular member is partially flattened to conform to the shape of theelongated opening in the second member prior to cutting the two opposingslots to form the locking tabs. Optionally, a reinforcing insert such asa tube of proper size is pressed into the opening between the spreadtabs to strengthen the connection.

13 Claims, 9 Drawing Figures PATENTED DEC 4 7 SHEET 1 0F 2 FIGURE 2FIGURE l FIGURE 4 Q. Q Q. (Q Q whonh o FIGURE 3 FIGURE 5 PATENTEDBEB4:915

SHEET 2 BF 2 FIGURE 6 FIGURE 9 ,FIGURE'YT HGURE a 1 STRUCTURAL TUBEASSEMBLY PRIOR APPLICATIONS This application is a Continuation-in-Partof U.S. Pat. application Ser. No. 120,107, filed Mar. 2, 1971 nowabandoned. su

BACKGROUND OF THE INVENTION Tubing assemblies are constructed for manypurposes such as fences, gates, antenna towers, pre-fab kennels,scaffolding, swing supports, and the like. One of the major use areasrelates to the construction of fences and related fixtures. Essentiallytubing assemblies for whatever purpose they might be used have in commonthe fact that they comprise a plurality of tubular members which areconnected to form the desired structure. Such connections must be strongand substantially rigid in order to impart structural integrity to thecompleted unit. In the past, the most accepted method of making suchconnections was to butt one member against another and weld themtogether. This is time consuming and does not adapt well to rapidproduction. Italso required that the work be performed at the factorywhere the necessary welding equipment is located, which greatly limitedthe amount of assembly that could be done at the construction site.

SUMMARY OF THE INVENTION The present invention provides a wide varietyof tubing assemblies in which a first tubular member is joined to asecond tubular member by providing an opening in .the wall of the secondtubular member through which the end of 'the first tubular memberextends. The end of the first member is generally flattened to resemblethe shape of the opening in the second member and slots are cut in theend of the first member to separate the two flattened surfaces into twolocking tabs which extend into the opening in the second member and arespread to substantially conform to the contour of the inside surface ofthe second tubular member, thus locking the members securely and rigidlytogether. The joint can be strengthened by providing an insert which ispressed between the spread locking tabs, thus holding them securely inplace.

I BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a first tubular memberabout to be inserted in an opening of a second tubular member.

FIG. 2 shows the completed connection.

FIG. 3 is a partial cross-section of FIG. 1 taken at A-A.

FIG. 4 is a partial cross-section of FIG. 2'taken at B-B.

FIG. 5 showsa completed gate assembly made according to this invention.

FIG. 6 is a partial cross-section similar to FIG. 4 except showing incross-section a tubular reinforcing insert in place.

FIG. 7 is a cross-section of FIG. 4 takenat C-C.

FIG. 8 is a tubular assembly having multiplerectangular units sharingcommon tubular members.

FIG. 9 is a cross-section of a tubing connection .in FIG. 8 taken at DD.

DESCRIPTION OF PREF ERRED EMBODIMENTS FIGS. 1 andfls how tubular membersready toform the connectionof this invention. "First tubular member 1has opposing portions of its side wall flattened 2 such that itscross-section conforms substantially to elongated opening 3 is secondtubular member 4. Two opposing slots or recesses 5 are cut in tube 1 ina manner such that flattened portions 2 are separated into locking tabs6 and 7.

FIGS. 2 and 4 show the completed connection. Tabs 6 and 7 extend throughlongitudinally elongated opening 3 of member 4 and are spread such thatthey substantially conform to the inside contour 8 of second tubularmember 4 firmly locking the tubular members together without the need ofwelding or of the use of screws, bolts, brackets, locking pins, and thelike.

FIG. 5 shows a gate constructed according to the present invention.Vertical members 10 and 11 correspond to tubular member 4 and areprovided with an elongated opening 3 in proximity to the top and bottom.The ends of horizontal members 12 and 13 are flattened to provide aslip-fit into opening 3 and are slotted to provide two locking tabs 6and 7.

A facile method of assembling the gate is to insert the pre-formed endsof members 12 and 13 into the elongated openings in members 10 and 11.At this stage the assembly can be held in a fixture. Then, as shown byphantom lines in FIG. 7, a tapered pin 15 is driven through the ends 16,17, 18 and 19 of members 10 and 11 in between tabs 6 and 7, thusspreading the tabs and forcing them into locking position against theinner surface 8 of members 10 and 11.

The gate frame is then provided with fencing 20 which is attached tomembers 10, 11, 12 and 13. For installation, the completed gate isprovided with hinges 21 and 22 and latch 23.

The rest of the fence can be assembled in the same manner as the gate.

As shown in FIG. 5, the connected tubular members are at right angleswith each other, but this is not necessary as the connection can beformed over a wide angle range.

In another embodiment of my invention, illustrated in FIG. 6, areinforcing insert '60 is press-fit into the space between spreadlocking tabs 6 and 7 in second tube member 4. Insert as shown is atubular insert but may be any suitable material such as wood or plasticpin. Also useful is a segment of split tubing which is compressed forinsertion and then allowed to expand against tabs 6 and 7.

In another embodiment the reinforcing insert 60 is a swedged end ofthird tubular member of the tubing assembly. By swedged, I mean that'theend of the tubular member is reduced in diameter by known means such asforcing the tube into a die having a circular opening of smallerdiameter than that of the tubular member. According to this embodiment,more complex tubular structures may be assembled without use of weldingor brackets, although such other attachment methods may be used inconjunction with my method. This embodiment of my invention permitsconstruction of :such things as pre-fab fence units containing more thanone rectangular frame. It is also useful in construction of suchassemblies as TV antenna towers made of three or four long verticaltubes each of which is crossbracedv to another of the vertical tubes.The lower end of upright tubular members are swedged and inserted intothe upper end of another upright tubular member forming long verticaltubes and at the same time reinforcing the connection of the cross-bracemembers which are connected to the upright tubular members in accordancewith this invention.

FIG. 8 shows a typical fence section suitable for use in assembling adog kennel. It is comprised of lower upright tubular members and 31 andhorizontal members 32 and 33 which together form a rectangular frame.Ends 34 and 35 of tubular member 33 are flattened and slotted to formopposed locking tabs and fit into an elongated opening in the top ofupright members 30 and 31. The locking tabs are spread to formconnections of this invention. One end 36 of member 32 is alsoflattened, slotted, and inserted into an elongated opening at the lowerend of upright member 30 wherein it is spread to form a connection ofthis invention. The lower end 37 of upright member 31 is flattened,slotted, and fit into an elongated opening near the end of member 32wherein it is spread to form a connection of this invention. A secondrectangular frame is constructed by inserting the lower swedged ends 38and 39 of upright members 40 and 41 in between the spread locking tabsinside the upper end of members 30 and 31. This should be a press-fit toform a secure joint. The joint formed is further illustrated in FIG. 9.Phantom lines show swedged end 39 of member 41 inserted in between thelocking tabs 6 and 7 of member 35. This forms a secure joint of threetubular members.

Upper horizontal tubular member 42 is flattened and slotted at end 43 toform opposed locking tabs as 6 and 7 in FIG. 3. These are inserted in anelongated opening in the side wall of member 40 near its upper end. Thelocking tabs are spread by driving in a tapered rod and a tubular insertis pressed in between the spread locking tabs to reinforce the joint asshown in FIG. 6.

At the opposite end 44 of member 42 an elongated opening is providedwhich receives the locking tabs formed by flattening and slotting theupper end of member 41. This completes a second rectangular framesharing common tubular member 33 with the first rectangular frame.

An opening suitable for the installation of a gate is next provided byinserting the swedged ends 45 and 46 of horizontal members 50 and 51 inbetween the spread locking tabs of members 41 and 31 within tubularmembers 42 and 32 forming a reinforced connection as illustrated in FIG.9. The opposite end 52 and 53 of members 50 and 51 are flattened andslotted to form locking tabs which are inserted in elongated openings inthe side wall and near the ends of tubular member 54. These locking tabsare spread inside member 54. Tubular reinforcing inserts are pressed inbetween the spread locking tabs to form a secure rigid joint as shown inFIG. 6.

From the foregoing description, it can be seen that a great many tubularframe assemblies can be fabricated using the connection provided by thisinvention. The number of such assemblies is limited only by theimagination and ingenuity of the fabricator.

I claim:

1. A structural tubing assembly comprising at least one substantiallyrigid connection of a first tubular member to a second tubular member,said connection comprising (A) an opening in the wall of said secondtubular member, the width of said opening being less than the insidediameter of said second tubular member, and (B) opposing longitudinalslots in the end of said first tubular member such that the wall betweensaid slots form two locking tabs, said tabs being positioned throughsaid opening and inside of said second tubular member and shaped toabruptly diverge and converge to substantially confon'n to and tightlycontact the inside surface of said second tubular member to preventangular and lateral distortion thereof forming a substantially rigidconnection of said first tubular member to said second tubular member.

2. A tubing assembly of claim 1 wherein said opening in the wall of saidsecond tubular member is longitudinally elongated and the opposing sidewalls of said first tubular member at the location at which it extendsthrough said opening in said second tubular member are flattened suchthat the cross-section of said first tubular member at said locationsubstantially conforms with said longitudinally elongated opening insaid second tubular member.

3. A tubing assembly of claim 1 further characterized by having acylindrical reinforcing insert tightly fitted between said two lockingtabs, said insert conforming with the inside contour of said two lockingtabs thereby holding said tabs tightly against the inside surface ofsaid second tubular member.

4. A tubing assembly of claim 3 wherein said reinforcing insert is anend of a third tubular member of said structural tubing assembly, saidend having a reduced outside diameter to conform with the inside contourof said two locking tabs.

5. A tubing assembly of claim 1 wherein said first and said secondtubular members have a substantially circular cross-section.

6. A tubing assembly of claim 5 wherein said opening in the wall of saidsecond tubular member is longitudinally elongated and the opposing sidewalls of said first tubular member at the location at which it extendsthrough said opening in said second tubular member are flattened suchthat the cross-section of said first tubular member at said locationsubstantially conforms with said longitudinally elongated opening insaid second tubular member.

7. A tubing assembly of claim 6 further characterized by having acylindrical reinforcing insert tightly fitted between said two lockingtabs, said insert conforming with the inside contour of said two lockingtabs thereby holding said tabs tightly against the inside surface ofsaid second tubular member.

8. A tubing assembly of claim 7 wherein said reinforcing insert is atubular member tightly fit between said two locking tabs.

9. A tubing assembly of claim 8 wherein said tubular member is an end ofa third tubular member of said structural tubing assembly, said endhaving a reduced outside diameter to conform with the inside contour ofsaid two locking tabs.

10. A substantially rectangular tubular frame assembly comprising fourtubular members, each of said members connected at both ends to anotherof said four tubular members to form a substantially rectangular frame,each of said connections comprising (A) a longitudinally elongatedopening in one of the connected members, the width of said opening beingless than the inside diameter of said one of the connected members, and(B) opposing longitudinal slots in the end of the other of saidconnected members such that the wall between said slots forms twolocking tabs, said tabs being inserted through said elongated openingand abruptly diverging and converging to substantially contabs therebyholding said tabs tightly against the inside surface of said one of theconnected members.

13. A tubular frame assembly of claim 12 wherein at least one of saidreinforcing inserts is an end of another tubular member which forms oneside of an adjoining tubular frame assembly, said adjoining tubularframe assembly sharing a common tubular member with said tubular frameassembly of claim 12, said end having a reduced outside diameter toconform with the inside contour of said two locking tabs.

1. A structural tubing assembly comprising at least one substantiallyrigid connection of a first tubular member to a second tubular member,said connection comprising (A) an opening in the wall of said secondtubular member, the width of said opening being less than the insidediameter of said second tubular member, and (B) opposing longitudinalslots in the end of said first tubular member such that the wall betweensaid slots form two locking tabs, said tabs being positioned throughsaid opening and inside of said second tubular member and shaped toabruptly diverge and converge to substantially conform to and tightlycontact the inside surface of said second tubular member to preventangular and lateral distortion thereof forming a substantially rigidconnection of said first tubular member to said second tubular member.2. A tubing assembly of claim 1 wherein said opening in the wall of saidsecond tubular member is longitudinally elongated and the opposing sidewalls of said first tubular member at the location at which it extendsthrough said opening in said second tubular member are flattened suchthat the cross-sEction of said first tubular member at said locationsubstantially conforms with said longitudinally elongated opening insaid second tubular member.
 3. A tubing assembly of claim 1 furthercharacterized by having a cylindrical reinforcing insert tightly fittedbetween said two locking tabs, said insert conforming with the insidecontour of said two locking tabs thereby holding said tabs tightlyagainst the inside surface of said second tubular member.
 4. A tubingassembly of claim 3 wherein said reinforcing insert is an end of a thirdtubular member of said structural tubing assembly, said end having areduced outside diameter to conform with the inside contour of said twolocking tabs.
 5. A tubing assembly of claim 1 wherein said first andsaid second tubular members have a substantially circular cross-section.6. A tubing assembly of claim 5 wherein said opening in the wall of saidsecond tubular member is longitudinally elongated and the opposing sidewalls of said first tubular member at the location at which it extendsthrough said opening in said second tubular member are flattened suchthat the cross-section of said first tubular member at said locationsubstantially conforms with said longitudinally elongated opening insaid second tubular member.
 7. A tubing assembly of claim 6 furthercharacterized by having a cylindrical reinforcing insert tightly fittedbetween said two locking tabs, said insert conforming with the insidecontour of said two locking tabs thereby holding said tabs tightlyagainst the inside surface of said second tubular member.
 8. A tubingassembly of claim 7 wherein said reinforcing insert is a tubular membertightly fit between said two locking tabs.
 9. A tubing assembly of claim8 wherein said tubular member is an end of a third tubular member ofsaid structural tubing assembly, said end having a reduced outsidediameter to conform with the inside contour of said two locking tabs.10. A substantially rectangular tubular frame assembly comprising fourtubular members, each of said members connected at both ends to anotherof said four tubular members to form a substantially rectangular frame,each of said connections comprising (A) a longitudinally elongatedopening in one of the connected members, the width of said opening beingless than the inside diameter of said one of the connected members, and(B) opposing longitudinal slots in the end of the other of saidconnected members such that the wall between said slots forms twolocking tabs, said tabs being inserted through said elongated openingand abruptly diverging and converging to substantially conform to theinside surface of said one of the connected members forming asubstantially rigid rectangular frame.
 11. A tubular frame assembly ofclaim 10 useful as a gate or fence section wherein fencing is positionedin the rectangular area formed by said four tubular members and isattached to said members.
 12. A tubular frame assembly of claim 10further characterized by having a cylindrical reinforcing insert tightlyfitted between said two locking tabs, said insert conforming with theinside contour of said two locking tabs thereby holding said tabstightly against the inside surface of said one of the connected members.13. A tubular frame assembly of claim 12 wherein at least one of saidreinforcing inserts is an end of another tubular member which forms oneside of an adjoining tubular frame assembly, said adjoining tubularframe assembly sharing a common tubular member with said tubular frameassembly of claim 12, said end having a reduced outside diameter toconform with the inside contour of said two locking tabs.